1. Technical Field
The present invention relates in general to a system and method for sensing the formation of tin whiskers. More particularly, the present invention relates to a system and method for using whisker detectors, which are integrated onto an assembly substrate, to detect tin whisker formations in an X direction, a Y direction, and a Z direction relative to the assembly substrate.
2. Description of the Related Art
New Restrictions of Hazardous Substances (RoHS) requirements are being established that eliminate the use of lead as a soldering material in electronic manufacturing processes. As such, manufacturers are developing processes to use tin as a soldering material. Tin, however, is prone to developing “whiskers,” which are electrically conductive, crystalline structures of tin that may cause shorts between trace lines and/or solder pads that results in erratic component failures.
A challenge found is that the formation of tin whiskers is not predictable. Some theories suggest that tin whiskers form from stress-induced manufacturing processes. Failures caused by tin whiskers, however, may not arise until later in a product's lifecycle. For example, tin whisker formations may not cause failures until years after being in the field. Once a failure occurs, a product may be shipped back to a manufacturing facility, where the tin whiskers are located using visual inspection.
What is needed, therefore, is a system and method that detects tin whiskers throughout a product's lifecycle prior to the tin whiskers causing component failures.